Oled backplate structure

ABSTRACT

The present invention provides an OLED backplate structure. Multiple auxiliary conducting layers contacting the cathode are provided under the cathode of the OLED, which can diminish the electrical resistance of the cathode to enhance the conductivity of the cathode and to even the in plane voltages. The uniformity of the OLED display can be improved to prevent the uneven brightness issue and to decrease the thickness of the cathode for saving the production cost.

FIELD OF THE INVENTION

The present invention relates to a display technology field, and moreparticularly to an OLED backplate structure.

BACKGROUND OF THE INVENTION

An OLED is an Organic Light Emitting Diodes Display possessingproperties of self-illumination, high brightness, wide view angle, highcontrast, flexibility and low power consumption, etc., and accordinglyhas been received more attentions. As being the display of nextgeneration, it has been gradually replaced traditional liquid crystaldisplays and widely applied in cellular phone screens, computerdisplays, full color TV, etc. OLED display technology is different fromthe traditional liquid crystal display technology and the back light isnot required. It utilizes an ultra thin organic material coating layerand a glass substrate, and theses organic material will illuminate whenthe current is conducted.

Please refer to FIG. 1, which is a sectional diagram of an OLEDbackplate structure according to prior art, comprising a substrate 100,a TFT layer 700 positioned on the substrate 100, a first isolation layer710 positioned on the TFT layer 700, a second isolation layer 720positioned on the first isolation layer 710, a first electrode 810positioned on the second isolation layer 720, a pixel definition layer830 positioned on the first electrode 810 and the second isolation layer720, a light emitting layer 900 positioned on the pixel definition layer830 and the first electrode 810, a photospacer 840 positioned on thepixel definition layer 830, a second electrode 820 positioned on thepixel definition layer 830, the photospacer 840 and the light emittinglayer 900.

The pixel definition layer 830 is provided with a first via 3110correspondingly above the first electrode 810, and the first isolationlayer 710 and the second isolation layer 720 are provided with a secondvia 3150 correspondingly above the TFT layer 700. The light emittinglayer 900 contacts the first electrode 810 through the first via 3110,and the first electrode 810 contacts the TFT layer 700 through thesecond via 3150.

In the aforesaid OLED backplate structure, the first electrode 810 isemployed as being a pixel electrode, which is an anode of the OLED, andthe second electrode 820 is employed as being a cathode of the OLED, andthe thickness of the second electrode 820 is thinner; particularly, inthe top light emitting type OLED backplate structure, the transparentelectrode has to be manufactured. Thus, a thinner second electrode 820is required. However, under the circumstance that the second electrode820 is thinner, the electrical resistance is larger, and particularly inthe large scale display, the in plane voltages which is uneven canhappen to influence the uniformity of the OLED display and cause issuesof uneven brightness (mura).

SUMMARY OF THE INVENTION

An objective of the present invention is to provide an OLED backplatestructure, of which the electrical resistance of the cathode is smallerand the conductivity is strong, and the in plane voltages are even. Theuniformity of the OLED display can be improved, and the cathode isthinner, and the light transmission is better, and the production costis low.

For realizing the aforesaid objective, the present invention provides anOLED backplate structure, comprising a substrate, a TFT layer positionedon the substrate, a first isolation layer positioned on the TFT layer, asecond isolation layer positioned on the first isolation layer, a firstelectrode positioned on the second isolation layer, a pixel definitionlayer positioned on the first electrode and the second isolation layer,a light emitting layer positioned on the pixel definition layer and thefirst electrode, a photospacer positioned on the pixel definition layer,a second electrode positioned on the pixel definition layer, thephotospacer and the light emitting layer;

multiple auxiliary conducting layers are provided to be apart with thefirst electrode under the second electrode, and the second electrodecontacts the auxiliary conducting layers.

The pixel definition layer is provided with a first via correspondinglyabove the first electrode, and the first isolation layer and the secondisolation layer are provided with a second via correspondingly above theTFT layer; the light emitting layer contacts the first electrode throughthe first via, and the first electrode contacts the TFT layer throughthe second via;

the first electrode is employed as being a pixel electrode, which is ananode of the OLED, and the second electrode is employed as being acathode of the OLED.

An auxiliary conducting layer is provided on the second isolation layer,and the pixel definition layer is provided with a third viacorrespondingly above the auxiliary conducting layer, and the secondelectrode contacts the auxiliary conducting layer through the third via.

The auxiliary conducting layer and the first electrode are manufacturedby employing the same mask.

An auxiliary conducting layer is provided on the first isolation layer,and the pixel definition layer and the second isolation layer areprovided with a third via correspondingly above the auxiliary conductinglayer, and the second electrode contacts the auxiliary conducting layerthrough the third via.

The auxiliary conducting layer is manufactured alone or manufacturedwith other conductive electrodes at the same time.

The first isolation layer is provided with a first auxiliary conductinglayer, and the second isolation layer is provided with a secondauxiliary conducting layer, and the pixel definition layer is providedwith a third via correspondingly above the second auxiliary conductinglayer, and the second isolation layer is provided with a fourth viacorrespondingly above the first auxiliary conducting layer; the secondauxiliary conducting layer contacts the first auxiliary conducting layerthrough the fourth via, and the second electrode contacts the secondauxiliary conducting layer through the third via.

Material of the auxiliary conducting layers is ITO.

The auxiliary conducting layers are distributed to appear to be acontinuous latticework, or constituted by multiple auxiliary conductingblocks arranged in spaces.

Arrangements of the respective multiple auxiliary conducting layers arethe same or different.

The present invention further provides an OLED backplate structure,comprising a substrate, a TFT layer positioned on the substrate, a firstisolation layer positioned on the TFT layer, a second isolation layerpositioned on the first isolation layer, a first electrode positioned onthe second isolation layer, a pixel definition layer positioned on thefirst electrode and the second isolation layer, a light emitting layerpositioned on the pixel definition layer and the first electrode, aphotospacer positioned on the pixel definition layer, a second electrodepositioned on the pixel definition layer, the photospacer and the lightemitting layer;

multiple auxiliary conducting layers are provided to be apart with thefirst electrode under the second electrode, and the second electrodecontacts the auxiliary conducting layers;

wherein the pixel definition layer is provided with a first viacorrespondingly above the first electrode, and the first isolation layerand the second isolation layer are provided with a second viacorrespondingly above the TFT layer; the light emitting layer contactsthe first electrode through the first via, and the first electrodecontacts the TFT layer through the second via;

the first electrode is employed as being a pixel electrode, which is ananode of the OLED, and the second electrode is employed as being acathode of the OLED;

wherein an auxiliary conducting layer is provided on the secondisolation layer, and the pixel definition layer is provided with a thirdvia correspondingly above the auxiliary conducting layer, and the secondelectrode contacts the auxiliary conducting layer through the third via;

wherein the auxiliary conducting layer and the first electrode aremanufactured by employing the same mask.

The benefits of the present invention are: in the OLED backplate of thepresent invention, multiple auxiliary conducting layers contacting thecathode are provided under the cathode of the OLED, which can diminishthe electrical resistance of the cathode to enhance the conductivity ofthe cathode and to even the in plane voltages. The uniformity of theOLED display can be improved to prevent the uneven brightness issue andto decrease the thickness of the cathode for saving the production cost.

In order to better understand the characteristics and technical aspectof the invention, please refer to the following detailed description ofthe present invention is concerned with the diagrams, however, providereference to the accompanying drawings and description only and is notintended to be limiting of the invention.

BRIEF DESCRIPTION OF THE DRAWINGS

The technical solution and the beneficial effects of the presentinvention are best understood from the following detailed descriptionwith reference to the accompanying figures and embodiments.

In drawings,

FIG. 1 is a sectional diagram of an OLED backplate structure accordingto prior art;

FIG. 2 is a sectional diagram of an OLED backplate structure accordingto the first embodiment of the present invention;

FIG. 3 is a sectional diagram of an OLED backplate structure accordingto the second embodiment of the present invention;

FIG. 4 is a sectional diagram of an OLED backplate structure accordingto the third embodiment of the present invention;

FIG. 5 is a top view diagram of one distribution way of the auxiliaryconducting layers according to the OLED backplate structure of thepresent invention;

FIG. 6 is a top view diagram of another distribution way of theauxiliary conducting layers according to the OLED backplate structure ofthe present invention.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

For better explaining the technical solution and the effect of thepresent invention, the present invention will be further described indetail with the accompanying drawings and the specific embodiments.

Please refer from FIG. 2 to FIG. 4. The present invention provides anOLED backplate structure, comprising a substrate 1, a TFT layer 70positioned on the substrate 1, a first isolation layer 71 positioned onthe TFT layer, a second isolation layer 72 positioned on the firstisolation layer 71, a first electrode 81 positioned on the secondisolation layer 72, a pixel definition layer 83 positioned on the firstelectrode 81 and the second isolation layer 72, a light emitting layer90 positioned on the pixel definition layer 83 and the first electrode81, a photospacer 84 positioned on the pixel definition layer 83, asecond electrode 82 positioned on the pixel definition layer 83, thephotospacer 84 and the light emitting layer 90.

Multiple auxiliary conducting layers are provided to be apart with thefirst electrode 81 under the second electrode 82, and the secondelectrode 82 contacts the auxiliary conducting layers.

Specifically, the pixel definition layer 83 is provided with a first via311 correspondingly above the first electrode 81, and the firstisolation layer 71 and the second isolation layer 72 are provided with asecond via 315 correspondingly above the TFT layer 70.

The light emitting layer 90 contacts the first electrode 81 through thefirst via 311, and the first electrode 81 contacts the TFT layer 70through the second via 315.

The first electrode 81 is employed as being a pixel electrode, which isan anode of the OLED, and the second electrode 82 is employed as being acathode of the OLED.

Specifically, material of the first electrode 81 is ITO (Indium TinOxide).

Please refer to FIG. 2 which is a sectional diagram of an OLED backplatestructure according to the first embodiment of the present invention. Anauxiliary conducting layer 85 is provided on the second isolation layer72, and the pixel definition layer 83 is provided with a third via 316correspondingly above the auxiliary conducting layer 85, and the secondelectrode 82 contacts the auxiliary conducting layer 85 through thethird via 316.

Specifically, the auxiliary conducting layer 85 and the first electrode81 can be manufactured by employing the same mask.

Specifically, material of the auxiliary conducting layer 85 can be ITOor other conductive materials.

Please refer to FIG. 3, which is a sectional diagram of an OLEDbackplate structure according to the second embodiment of the presentinvention. An auxiliary conducting layer 85′ is provided on the firstisolation layer 71, and the pixel definition layer 83 and the secondisolation layer 72 are provided with a third via 316′ correspondinglyabove the auxiliary conducting layer 85′, and the second electrode 82contacts the auxiliary conducting layer 85′ through the third via 316′.

Specifically, the auxiliary conducting layer 85′ can be manufacturedalone or manufactured with other conductive electrodes, such as thesource/the drain of the TFT layer 70 at the same time.

Specifically, material of the auxiliary conducting layer 85′ can be ITOor other conductive materials.

Please refer to FIG. 4, which is a sectional diagram of an OLEDbackplate structure according to the third embodiment of the presentinvention. The first isolation layer 71 is provided with a firstauxiliary conducting layer 851, and the second isolation layer 72 isprovided with a second auxiliary conducting layer 852, and the pixeldefinition layer 83 is provided with a third via 316″ correspondinglyabove the second auxiliary conducting layer 852, and the secondisolation layer 72 is provided with a fourth via 317 correspondinglyabove the first auxiliary conducting layer 851; the second auxiliaryconducting layer 852 contacts the first auxiliary conducting layer 851through the fourth via 317, and the second electrode 82 contacts thesecond auxiliary conducting layer 852 through the third via 316″.

Specifically, material of the first auxiliary conducting layer 851 andthe second auxiliary conducting layer 852 can be ITO or other conductivematerials.

Significantly, in the aforesaid first to third embodiments, theauxiliary conducting layers can be continuously distributed as shown inFIG. 5, being distributed to appear to be a continuous latticework orcontinuously distributed to be other appearances; the auxiliaryconducting layers can be non-continuously distributed as shown in FIG.6, being constituted by multiple auxiliary conducting blocks arranged inspaces. In the aforesaid third embodiment, arrangements of therespective multiple auxiliary conducting layers can be the same or canbe different.

In conclusion, in the OLED backplate of the present invention, multipleauxiliary conducting layers contacting the cathode are provided underthe cathode of the OLED, which can diminish the electrical resistance ofthe cathode to enhance the conductivity of the cathode and to even thein plane voltages. The uniformity of the OLED display can be improved toprevent the uneven brightness issue and to decrease the thickness of thecathode for saving the production cost.

Above are only specific embodiments of the present invention, the scopeof the present invention is not limited to this, and to any persons whoare skilled in the art, change or replacement which is easily derivedshould be covered by the protected scope of the invention. Thus, theprotected scope of the invention should go by the subject claims.

What is claimed is:
 1. An OLED backplate structure, comprising asubstrate, a TFT layer positioned on the substrate, a first isolationlayer positioned on the TFT layer, a second isolation layer positionedon the first isolation layer, a first electrode positioned on the secondisolation layer, a pixel definition layer positioned on the firstelectrode and the second isolation layer, a light emitting layerpositioned on the pixel definition layer and the first electrode, aphotospacer positioned on the pixel definition layer, a second electrodepositioned on the pixel definition layer, the photospacer and the lightemitting layer; multiple auxiliary conducting layers are provided to beapart with the first electrode under the second electrode, and thesecond electrode contacts the auxiliary conducting layers.
 2. The OLEDbackplate structure according to claim 1, wherein the pixel definitionlayer is provided with a first via correspondingly above the firstelectrode, and the first isolation layer and the second isolation layerare provided with a second via correspondingly above the TFT layer; thelight emitting layer contacts the first electrode through the first via,and the first electrode contacts the TFT layer through the second via;the first electrode is employed as being a pixel electrode, which is ananode of the OLED, and the second electrode is employed as being acathode of the OLED.
 3. The OLED backplate structure according to claim1, wherein an auxiliary conducting layer is provided on the secondisolation layer, and the pixel definition layer is provided with a thirdvia correspondingly above the auxiliary conducting layer, and the secondelectrode contacts the auxiliary conducting layer through the third via.4. The OLED backplate structure according to claim 3, wherein theauxiliary conducting layer and the first electrode are manufactured byemploying the same mask.
 5. The OLED backplate structure according toclaim 1, wherein an auxiliary conducting layer is provided on the firstisolation layer, and the pixel definition layer and the second isolationlayer are provided with a third via correspondingly above the auxiliaryconducting layer, and the second electrode contacts the auxiliaryconducting layer through the third via.
 6. The OLED backplate structureaccording to claim 5, wherein the auxiliary conducting layer ismanufactured alone or manufactured with other conductive electrodes atthe same time.
 7. The OLED backplate structure according to claim 1,wherein the first isolation layer is provided with a first auxiliaryconducting layer, and the second isolation layer is provided with asecond auxiliary conducting layer, and the pixel definition layer isprovided with a third via correspondingly above the second auxiliaryconducting layer, and the second isolation layer is provided with afourth via correspondingly above the first auxiliary conducting layer;the second auxiliary conducting layer contacts the first auxiliaryconducting layer through the fourth via, and the second electrodecontacts the second auxiliary conducting layer through the third via. 8.The OLED backplate structure according to claim 1, wherein material ofthe auxiliary conducting layers is ITO.
 9. The OLED backplate structureaccording to claim 1, wherein the auxiliary conducting layers aredistributed to appear to be a continuous latticework, or constituted bymultiple auxiliary conducting blocks arranged in spaces.
 10. The OLEDbackplate structure according to claim 1, wherein arrangements of therespective multiple auxiliary conducting layers are the same ordifferent.
 11. An OLED backplate structure, comprising a substrate, aTFT layer positioned on the substrate, a first isolation layerpositioned on the TFT layer, a second isolation layer positioned on thefirst isolation layer, a first electrode positioned on the secondisolation layer, a pixel definition layer positioned on the firstelectrode and the second isolation layer, a light emitting layerpositioned on the pixel definition layer and the first electrode, aphotospacer positioned on the pixel definition layer, a second electrodepositioned on the pixel definition layer, the photospacer and the lightemitting layer; multiple auxiliary conducting layers are provided to beapart with the first electrode under the second electrode, and thesecond electrode contacts the auxiliary conducting layers; wherein thepixel definition layer is provided with a first via correspondinglyabove the first electrode, and the first isolation layer and the secondisolation layer are provided with a second via correspondingly above theTFT layer; the light emitting layer contacts the first electrode throughthe first via, and the first electrode contacts the TFT layer throughthe second via; the first electrode is employed as being a pixelelectrode, which is an anode of the OLED, and the second electrode isemployed as being a cathode of the OLED; wherein an auxiliary conductinglayer is provided on the second isolation layer, and the pixeldefinition layer is provided with a third via correspondingly above theauxiliary conducting layer, and the second electrode contacts theauxiliary conducting layer through the third via; wherein the auxiliaryconducting layer and the first electrode are manufactured by employingthe same mask.
 12. The OLED backplate structure according to claim 11,wherein material of the auxiliary conducting layers is ITO.
 13. The OLEDbackplate structure according to claim 11, wherein the auxiliaryconducting layers are distributed to appear to be a continuouslatticework, or constituted by multiple auxiliary conducting blocksarranged in spaces.